Systems and Methods for Blending Hydrocarbons into Gasoline

ABSTRACT

A system for forming blended gasoline from gasoline and butane includes a gasoline inlet configured to receive the gasoline, a butane inlet configured to receive the butane, and a first mixing section in which the gasoline and the butane mix to thereby form a rough blended gasoline. A second mixing section downstream from the first mixing section further mixes the rough blended gasoline with additional amounts of the gasoline or the butane until a final blended gasoline forms in the second mixing section. The final blended gasoline dispenses from the second mixing section via an outlet.

CROSS-REFERENCE TO RELATED APPLICATION

The present disclosure is based on and claims priority to U.S.Provisional Patent Application No. 62/800,875 filed Feb. 4, 2019, thedisclosure of which is incorporated herein by reference.

FIELD

The present disclosure relates to the petroleum industry, andspecifically to systems and methods for blending hydrocarbons intogasoline.

BACKGROUND

Businesses and consumers are commonly sold blended gasoline that isformed with rough gasoline (e.g., unblended gasoline) and lower costcomponents, such as hydrocarbons (e.g., butane), to thereby lower theoverall cost of the gasoline. The lower cost components added to therough gasoline often have a Reid Vapor Pressure (RVP) that is greaterthan the RVP of the rough gasoline, and accordingly, the total RVP ofthe blended gasoline increases as the lower cost components are added tothe rough gasoline.

Government and environmental rules and regulations dictate the maximumallowable RVP or range of RVP of the blended gasoline. These rules andregulations can vary state-to-state, be based on geographic location,and/or be based on the calendar season. For instance, the maximumallowable RVP permitted can be seasonally dependent such that greaterfractions of the lower cost component and a higher RVP of the blendedgasoline is permissible during winter months.

Accordingly, companies that sell blended gasoline attempt to produce theblended gasoline at the maximum allowable RVP to thereby lower the priceof the blended gasoline that will be sold. However, these companies mustmonitor the RVP of the blended gasoline to avoid fines for sellingblended gasoline with RVP above the maximum allowable RVP (or outside arequired RVP range). If a company does sell blended gasoline having aRVP greater than the maximum allowable RVP, the company can be finedand/or the company's reputation may be damaged. As such, it isadvantageous for companies to use systems and methods that blend roughgasoline with lower cost components such that the blended gasoline soldis at (or close too) the maximum allowable RVP. Also, it is advantageousfor the systems to quickly and efficiently change RVP of the blendedgasoline without causing plant shutdowns or loss of product.

An example of a conventional system for blending gasoline is describedin U.S. Pat. No. 9,795,935 (which is incorporated herein by reference inentirety). The system disclosed in U.S. Pat. No. 9,795,935 uses twotanks in which rough gasoline and butane are blended to form the blendedgasoline. When the blended gasoline mixed in the two tanks isoff-specification (e.g., the RVP of the blended gasoline exceeds themaximum allowable RVP), the contents of the tanks must be circulatedback through both tanks while additional amounts of the rough gasolineand/or the butane is added to the blended gasoline. The circulationprocess can be time-consuming and lead to inefficiencies in the system.

This Background is intended to introduce various aspects of the art,which may be associated with the present disclosure to thereby assist inproviding a framework to facilitate a better understanding of particularaspects of the present disclosure. Accordingly, it should be understoodthat this Background should be read in this light, and not necessarilyas admissions of prior art.

SUMMARY

This Summary is provided to introduce a selection of concepts that arefurther described below in the Detailed Disclosure. This Summary is notintended to identify key or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in limiting the scope ofthe claimed subject matter.

In certain examples, a system for forming blended gasoline from gasolineand butane includes a gasoline inlet configured to receive the gasoline,a butane inlet configured to receive the butane, and a first mixingsection in which the gasoline and the butane mix to thereby form a roughblended gasoline. A second mixing section downstream from the firstmixing section further mixes the rough blended gasoline with additionalamounts of the gasoline or the butane until a final blended gasolineforms in the second mixing section. The final blended gasoline dispensesfrom the second mixing section via an outlet.

In certain examples, a system for forming blended gasoline from gasolineand butane includes a gasoline inlet configured to receive gasoline suchthat the gasoline is conveyed along a first gasoline flow path and asecond gasoline flow path and a butane inlet configured to receive thebutane such that the butane is conveyed along a first butane flow pathand a second butane flow path. A first mixing section receives gasolinefrom the first gasoline flow path, receives the butane from the firstbutane flow path, mixes the gasoline and the butane to thereby form arough blended gasoline, and dispenses the rough blended gasoline. Asecond mixing section downstream from the first mixing section receivesthe rough blended gasoline from the first mixing section, receives thegasoline from the second gasoline flow path, receives the butane fromthe second butane flow path, mixes the gasoline and/or the butane withthe rough gasoline to thereby form a final blended gasoline, anddispenses the final blended gasoline. The final blended gasolinedispenses through an outlet, and a check valve is configured to permitthe rough blended gasoline to flow downstream into the second mixingsection and prevent the blended gasoline in the second mixing sectionfrom flowing upstream into the first mixing section. A gasoline analyzeris configured to analyze the blended gasoline in the second mixingsection and further output data pertaining to characteristics of theblended gasoline in the second mixing section. A controller isconfigured to open and close a first valve and a second valve based onthe data from the gasoline analyzer. The controller closes the firstvalve and opens the second valve when the final blended gasoline isformed in the second mixing section; and opens the first valve andcloses the second valve such that the blended gasoline in the secondmixing section circulates therein. The final blended gasoline is formedwhen the blended gasoline in the second mixing section has a Reid VaporPressure (RVP) that is within a threshold less than a maximum allowableRVP. The blended gasoline in the second mixing section can be circulatedin the second mixing section as the additional amounts of the gasolineor the butane mix with the rough blended gasoline.

In certain examples, a method for forming blended gasoline includes thesteps of receiving at a gasoline inlet gasoline from a gasoline supply,receiving at a butane inlet butane from a butane supply, mixing thegasoline and the butane in a first mixing section to thereby form arough blended gasoline, and dispensing the rough blended gasoline to asecond mixing section. The method can further include mixing the roughblended gasoline with additional amounts of the gasoline or the butaneuntil a final blended gasoline forms in the second mixing section anddispensing, via an outlet, the final blended gasoline from the secondmixing section.

Various other features, objects, and advantages will be made apparentfrom the following description taken together with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is described with reference to the followingFIGURE.

FIG. 1 is a schematic view of a system according to one exampleembodiment of the present disclosure.

DETAILED DISCLOSURE

The present inventor has observed that existing conventional systems forblending rough gasoline with another component, such as hydrocarbons(e.g., butane), are ineffective at forming blended gasoline at a maximumallowable RVP. Furthermore, the present inventor has observed thatexisting conventional systems are often large and require an extendedperiod of time to form the blended gasoline and adjust the RVP of theblended gasoline to the maximum allowable RVP. As such, the presentinventor has endeared to develop improved systems for blending roughgasoline with another component, such as hydrocarbons (e.g., butane), toproduce blended gasoline at or near a maximum allowable RVP.Accordingly, the present inventor has developed improved systems andmethods, described hereinbelow, for quickly and efficiently producingblended gasoline that conforms with (or closely matches) applicablerules and regulations, including a maximum allowable RVP of the blendedgasoline.

In certain examples, the systems and methods described hereinbelow allowfor greater blending precision to maximize the butane content in theblended gasoline while providing assurances that the blended gasolineremains in compliance with the applicable RVP rules and regulations. Thesystems and methods described hereinbelow can also increase or decreasethe RVP in a second stage or section of the blending process such thatonly on-specification blended gasoline is loaded onto tanker trucks andsold to consumers. The systems and methods described hereinbelow canalso provide volume buffers to smooth out changes as the composition ofthe blended gasoline changes and increase precision (e.g. closely matchthe specification) of the blended gasoline. The systems and methodsdescribed hereinbelow can also quickly react to adjust the amount ofrough gasoline and butane added to the system to reduce downtime.Furthermore, the systems and methods described hereinbelow can quicklystop flow of the blended gasoline to the tanker trucks when the blendedgasoline is off-specification and/or not at the maximum allowable RVP.In certain examples, the system of the present disclosure have smallerfootprints than conventional systems.

FIG. 1 is a schematic view of an example system 10 that blends roughgasoline with a hydrocarbon, such as butane, to form a blended gasoline.The system 10 includes a rough gasoline inlet 14 that receives gasolinefrom a gasoline supply 15 and an additive inlet 44 that receives anadditive, such as butane, from an additive supply 45. Note that whilethe system 10 depicted in FIG. 1 and described hereinbelow blends roughgasoline with butane to thereby form the blended gasoline, otheradditive fluids may be received into the system 10 and blended together(e.g., different types of hydrocarbons, etc.) to form the blendedgasoline.

The rough gasoline is conveyed downstream from the rough gasoline inlet14 to a rough gasoline dispensing section 16 that dispenses the roughgasoline to a first mixing section 71 and a second mixing section 82.Similarly, the butane is conveyed downstream from the butane inlet 44 toa butane dispensing section 46 that dispenses the butane to the firstmixing section 71 and the second mixing section 82. The rough gasolineand the butane are mixed together in each of the mixing sections 71, 82(described further herein) to form the blended gasoline which isconveyed to and dispensed from a blended gasoline outlet 100. Inparticular, the first mixing section 71 forms an initial or roughblended gasoline, and the second mixing section 82 mixes additionalamount of rough gasoline and/or butane into the rough blended gasolinefrom by the first mixing section 71 to thereby further refine and/orfine-tune the rough blended gasoline into a finished or final blendedgasoline that is blended to the required specification (e.g.,on-specification) and/or the maximum allowable RVP or within a range ofthe maximum allowable RVP (e.g., 1.0%-5.0% lower than the maximumallowable RVP). The system is designed to accurately achieve the RVPtarget; however, additional analyzers and sensors may be included in thesystem 10 that are dedicated to specific target constituents and operateunder the same control philosophy to allow the control and manipulationof additional specification targets, such as sulfur or renewable streams(e.g., bio-butanol or ethanol). In one example, information fromanalyzer 150 may be used to control pumping and modulating of ethanol.

The final blended gasoline is then dispensed from the second mixingsection 82 to one or more truck racks 102 such that the final blendedgasoline can be loaded onto tanker trucks. In the depicted example, thesystem 10 also includes one or more ethanol injectors 11 that injectethanol into the blended gasoline upstream of the truck racks 102.Details of the various sections and components of the systems 10 thatare briefly described above are described in greater detail hereinbelow.

As is briefly mentioned above, the rough gasoline dispensing section 16conveys and dispenses the rough gasoline to each mixing section 71, 82.The rough gasoline conveys past a rough gasoline analyzer 18 that isconfigured to analyze the characteristics (e.g., RVP, etc.) of the roughgasoline. The rough gasoline is then conveyed through a T-pipe 19 to oneof two parallel branches or flow paths, namely a first branch 21 and asecond branch 22. The first branch 21 includes a pump 25 that conveys(e.g., pumps) the rough gasoline, a flow meter 26 that monitors flow ofthe rough gasoline through the first branch 21, and a valve 27 thatselectively opens and closes to thereby permit or modulate or control orprevent conveyance of the rough gasoline to a first rough gasoline checkvalve 74 in the first mixing section 71. Similarly, the second branch 22includes a pump 35 that conveys (e.g., pumps) the rough gasoline, a flowmeter 36 that monitors flow of the rough gasoline through the secondbranch 22, and a valve 37 that selectively opens and closes to therebypermit or modulate or control or prevent conveyance of the roughgasoline to a second rough gasoline check valve 84 in the second mixingsection 82. Valves 27, 37, 57, 67 generally act as control valves thatcan modulate between 0% and 100% flow as system 10 may require.

The butane dispensing section 46 is similar to the rough gasolinedispensing section 16 and has similar components. The butane dispensingsection 46 conveys and dispenses the butane to the first mixing section71 and the second mixing section 82. The butane from the butane inlet 44is conveyed through a T-pipe 49 to one of two parallel branches, namelya first branch 51 and a second branch 52. The first branch 51 includes apump 55 that conveys (e.g., pumps) the butane, a flow meter 56 thatmonitors flow of the butane through the first branch 51, and a valve 57that selectively opens and closes to thereby permit or modulate orcontrol or prevent, conveyance of the butane to a first butane checkvalve 75 in the first mixing section 71. Similarly, the second branch 52includes a pump 65 that conveys (e.g., pumps) the butane, a flow meter66 that monitors flow of the butane through the second branch 52, and avalve 67 that selectively opens and closes to thereby permit or modulateor control or prevent conveyance of the butane to a second butane checkvalve 85 in the second mixing section 82.

The rough gasoline and the butane conveyed to first mixing section 71from the rough gasoline dispensing section 16 and the butane dispensingsection 46, respectively, are mixed together in the first mixing section71 to form the preliminary or rough blended gasoline. The rough gasolineand the butane are mixed together with a first mixing device 77 (e.g., astatic inline mixer) to thereby form the rough blended gasoline. Therough blended gasoline is then dispensed from the mixing device 77 to aninlet check valve 88 of the second mixing section 82. The rough blendedgasoline dispensed to the inlet check valve 88 is mixed to have certaincharacteristics (e.g., RVP, etc.) that are close to the specificationand/or the maximum allowable RVP of the blended gasoline that should beformed by the system 10 and will be dispensed from the outlet 100. Inone non-limiting example, the rough blended gasoline dispensed to theinlet check valve 88 has an RVP that is slightly lower than the maximumallowable RVP of the final blended gasoline to be formed by the system10.

As is briefly mentioned above, the rough blended gasoline is furtherrefined or fine-tuned in the second mixing section 82 by addingadditional amounts of rough gasoline and/or butane to thereby fine-tunethe characteristics and the RVP of the rough blended gasoline to conformwith or closely match the specification and/or the maximum allowable RVPof the final blended gasoline that will be dispensed through the outlet100. During operation of the system 10, the rough blended gasoline fromthe first mixing section 71 is conveyed through the inlet check valve 88of the second mixing section 82 and then circulated in a loop by a pump89 through T-pipe 91, a second mixing device 90 (e.g., a static inlinemixer), a finishing tank 92 (e.g., a pressure tank), a second T-pipe 93,and/or a check valve 94. As the rough blended gasoline circulatesthrough the loop of the second mixing section 82, additional amounts ofthe rough gasoline are added to the rough blended gasoline via thesecond rough gasoline check valve 84 when the valve 37 opens. Similarly,additional amounts of the butane are added to via the second butanecheck valve 85 as the valve 67 opens. Note that in certain examples, theblended gasoline in the second mixing section 82 may include volumes ofthe rough blended gasoline, the final blended gasoline, and/or anintermediate blended gasoline that has characteristics between the roughblended gasoline and the final blended gasoline. The amounts/volumes ofthe different blended gasolines may change as rough gasoline and/orbutane is added, as noted above. Also, in certain examples the number ofcirculations of the blended gasoline through the second mixing section82 may vary. For example, the blended gasoline may circulate oncethrough the second mixing section 82. In another example, the blendedgasoline may circulate more than once through the second mixing section82. In still another example, the blended gasoline may not circulatethrough the second mixing section 82 (e.g., the rough blended gasolineis mixed with the gasoline and/or butane such that the final blendedgasoline forms and flows directly through the second valve 99 and doesnot flow through the first valve 89).

The valves 37, 67 are controlled by a controller 120 (described furtherhereinbelow) which receives feedback signals (e.g., a closed feedbackloop) from a first analyzer 96 that is configured to analyze the blendedgasoline upstream of the second rough gasoline check valve 84 and thesecond butane check valve 85 and a second analyzer 97 that analyzes theblended gasoline downstream of the second rough gasoline check valve 84,the second butane check valve 85, and the second mixing device 90. Basedon the feedback from the analyzers 96, 97, the valves 37, 67 open andclose such that the additional amounts of the rough gasoline and/or thebutane are dispensed into the second mixing section 82, as describedabove. Accordingly, the characteristics and/or the maximum allowable RVPof the blended gasoline being circulated in the second mixing section 82can be fine-tuned to specification of the final blended gasoline.

Once the blended gasoline circulating through the second mixing section82 conforms with or closely matches the required specification and/orthe maximum allowable RVP of the final blended gasoline, a first valve98 closes and a second valve 99 opens such that the final blendedgasoline is conveyed through the second T-pipe 93 and the second valve99 to the outlet 100 (note that further details of the valves 98, 99 aredescribed hereinbelow). The final blended gasoline is then conveyed tothe truck racks 102 and is loaded into tanker trucks.

Operation of the components in the rough gasoline dispensing section 16,the butane dispensing section 46, the first mixing section 71, and/orthe second mixing section 82 are controlled by at least one programmablelogic controller 120 (hereinafter referred to as “controller”). Thecontroller 120 is depicted in FIG. 1 with a first stage section and asecond stage section, each of which is connected, via wired or wirelesslinks 122, to different components of the system 10. The controller 120includes a memory and a processor and may be connected to a user inputdevice 124 (e.g., touchscreen display, personal computer terminal) thatreceives inputs from an operator. In certain examples, the first andsecond stage sections of the controller 120 are separated into twoseparate programmable logic controllers. In certain examples, thecontroller 120 is in communication with an existing site automationsystem 126.

An example operational sequence of the system 10 for forming anddispensing the final blended gasoline having or closely matching therequired specification of the final blended gasoline to be dispensed viathe outlet 100 is described hereinbelow. Note that a person of ordinaryskill in the art will recognize that various equivalents, alternatives,and/or modifications may be made to the operation of the system 10 basedon the types of fluids mixed by the system 10 and required specificationand the maximum allowable RVP of the final blended gasoline.

In operation, the operator inputs the required specification for thefinal blended gasoline into the user input device 124. The requiredspecification for the final blended gasoline can include requiredcharacteristics (e.g., amounts of specified chemicals, percentage ofspecified chemical, etc.) and/or a maximum allowable RVP that aredictated by applicable rules and/or regulations, the type of components(e.g., butane) that are blended with the gasoline, the amount or volumeof the final blended gasoline to be dispensed, and/or includes otherregulated or targeted components such as sulfur or proprietary additivestreams. In the example described below, the system 10 is designed toform the final blended gasoline with the maximum allowable RVP. However,a person of ordinary skill in the art will recognize that the system 10is capable of forming the final blended gasoline such that the finalblended gasoline has any number desired characteristics based on anytype and/or number of factors, rules, and/or regulations.

Based on the user input, the controller 120 controls the pump 25 of therough gasoline dispensing section 16 and the pump 55 of the butanedispensing section 46 to thereby convey the rough gasoline and thebutane through the first rough gasoline check valve 74 and the firstbutane check valve 75, respectively, to the first mixing device 77. Theamount or volume of the rough gasoline and the butane conveyed to thefirst mixing device 77 is based on the characteristics (e.g., chemicalproperties, approximate RVP of each fluid, viscosity) of the roughgasoline and the butane. These characteristics are stored on the memoryof the controller 120 and/or are determined based on feedback receivedfrom the rough gasoline analyzer 18 and/or flow meters 26, 56. Based onthe characteristics of the rough gasoline and the butane and/or thefeedback received from the rough gasoline analyzer 18 and/or flow meters26, 56, the controller 120 controls (e.g., opens, closes) the valves 27,57 such that the rough gasoline and the butane mix at a ratio that isprojected or estimated by the controller 120 to closely match therequired specification and/or maximum allowable RVP of the final blendedgasoline and thereby form a preliminary or rough blended gasoline. Incertain examples, the controller 120 is configured to control the amountof the rough gasoline and/or the butane mixed in the first mixing device77 such that the blended gasoline is slightly below the requiredspecification and/or the maximum allowable RVP. In certain examples, thecontroller is configured to conduct a threshold analysis based on datafrom the analyzer(s) and determine if the blended gasoline within thesecond mixing section 82 is within a predetermined threshold of thefinal blended gasoline. In one instance, the predetermined threshold ofthe final blended gasoline is less than the maximum allowable RVP.

The rough blended gasoline is then dispensed into the second mixingsection 82 via the inlet check valve 88, as noted above, circulatedthrough the second mixing section 82, and possibly stored in the tank92. The tank 92 is configured to further mix the blended gasoline withinitself, and in some examples, the tank 92 acts as a “buffer” that storesa volume of the blended gasoline. Furthermore, the volume of the blendedgasoline in the tank may fluctuate (e.g., the volume of the blendedgasoline in the tank 92 increases and/or decreases) based on the amountor volume of the final blended gasoline dispensed via the outlet 100, asnoted above. For example, the volume of the blended gasoline in the tank92 increases when the second valve 99 is closed and as the rough blendedgasoline is continuously received from the first mixing device 77. Inanother example, the amount of the blended gasoline in the tank 92decreases when the first valve 98 is closed and the amount of the finalblended gasoline dispensed via the outlet 100 is greater than the amountof the rough blended gasoline is received from the first mixing device77. Note that in periods of plant closure and/or maintenance the blendedgasoline may not circulate through the second mixing section 82.

As the blended gasoline is circulated through the second mixing section82, the first analyzer 96 and/or the second analyzer 97 providedfeedback to the controller 120 pertaining to the characteristics of theblended gasoline being circulated. Based on the feedback, the controller120 is configured to either dispense the final blended gasoline to theoutlet 100 (when the specification of the final blended gasoline hasbeen met) or add additional amounts of the rough gasoline and/or thebutane to the blended gasoline to thereby change the characteristicsand/or the RVP of the blended gasoline being circulated. Specifically,if the controller 120 determines that the blended gasoline beingcirculated in the second mixing section 82 is the final blended gasoline(that is the blended gasoline being circulated is at the requiredspecification and/or at the maximum allowable RVP and thereby the finalblended gasoline), the controller 120 will close the first valve 98 andopen the second valve 99 such that the final blended gasoline does notcirculate through the second mixing section 82 and is instead dispensedvia the outlet 100. As the final blended gasoline is dispensed, thevolume of the final blended gasoline in the tank 92 may decrease and/oradditional amounts of the rough blended gasoline may be formed by thefirst mixing device 77 and added to the second mixing section 82. As thefinal blended gasoline dispenses, the first analyzer 96 and/or thesecond analyzer 97 continuously provided feedback to controller 120regarding the characteristics of the blended gasoline dispensing via theoutlet 100

If the controller 120 determines, based on feedback from the firstanalyzer 96 and/or the second analyzer 97, that the blended gasoline isno longer at the required specification (or within a threshold range)and/or the maximum allowable RVP relative to the final blended gasoline,the controller 120 closes the second valve 99 to immediately stop theflow of the blended gasoline to the outlet 100 and open the first valve98 such that the blended gasoline is not dispensed via the outlet 100.Instead, the blended gasoline in the second mixing section 82 iscirculated therein. The controller 120 then determines how to bestadjust the blended gasoline in the second mixing section 82 to thespecification and/or increase or decrease the RVP of the blendedgasoline to the maximum RVP. For example, the controller 120 can beconfigured to add additional amounts of rough gasoline and/or butane tothe blended gasoline in the second mixing section 82 to thereby adjust(e.g., “fine-tune”) the blended gasoline to the required specificationand the maximum RVP such that the final blended gasoline is once againformed and can be dispensed via the outlet 100.

In one example, if the RVP of the blended gasoline in the second mixingsection 82 is lower than the maximum RVP, the controller opens the valve67 and controls the pump 65 of the butane dispensing section 46 toconvey additional amount of butane directly into the second mixingsection 82 via the second butane check valve 85. The controller 120 mayalso receive feedback from the flow meter 66 such that the amount of thebutane added is continuously monitored. After an amount of additionalbutane estimated by the controller 120 to increase the RVP of theblended gasoline in the second mixing section 82 to the maximum RVP isadded to the second mixing section 82, the controller 120 monitorsfeedback from the first analyzer 96 and/or the second analyzer 97 todetermine if the RVP of the blended gasoline in the second mixingsection 82 is now at the maximum RVP and thus meet the speciation of thefinal blended gasoline. If RVP of the blended gasoline in the secondmixing section 82 is at the maximum RVP (e.g., the blended gasolinebeing circulated in the second mixing section 82 is the final blendedgasoline), the controller 120 closes the first valve 98 and opens thesecond valve 99 to thereby dispense the final blended gasoline via theoutlet 100, as described above. However, if the RVP of the blendedgasoline in the second mixing section 82 is still lower than the maximumallowable RVP, additional amounts of butane can be added, as describedabove, until the RVP of the blended gasoline in the second mixingsection 82 is at or closely matches the maximum RVP.

In another example, if the RVP of the blended gasoline in the secondmixing section 82 is higher than the maximum RVP, the controller 120opens the valve 37 and controls the pump 35 of the rough gasolinedispensing section 16 to thereby convey additional amounts of the roughgasoline directly into the second mixing section 82 via the second roughgasoline check valve 84. The controller 120 receives feedback from theflow meter 36 so that the amount of rough gasoline added is continuouslymonitored. After an amount of additional rough gasoline estimated by thecontroller 120 to decrease the RVP of the blended gasoline in the secondmixing section 82 to the maximum RVP is added to the second mixingsection 82, the controller 120 monitors feedback from the first analyzer96 and/or the second analyzer 97 to determine if the blended gasoline inthe second mixing section 82 is now at the maximum RVP and thus meet thespeciation of the final blended gasoline. If the RVP of the blendedgasoline is at the maximum RVP, the controller 120 closes first valve 98and opens the second valve 99 such that the final blended gasolinedispenses via the outlet 100, as described above. However, if the RVP ofthe blended gasoline in the second mixing section 82 is still higherthan the maximum allowable RVP, additional amount of the rough gasolineis added to the blended gasoline the second mixing section 82, as notedabove.

By opening and closing the second valve 99 based on continuous feedbackfrom the analyzers 96, 97, the system 10 is capable of quickly formingthe final blended gasoline at the required specification and/or with themaximum RVP. Furthermore, the system 10 is thereby capable of reducingor minimizing the amount of off-specification blended gasoline and/orblended gasoline not at the maximum RVP dispensed through the outlet100. Likewise, this system 10 can provide an improved ability to attainand/or control at the target to a tighter tolerance and is better ableto provide a more robust delivery reliability through the use of thefinishing tank 92 and the associated control logic, and being able torun control valves in a tighter range of their best control range.

In certain examples, the system 10 includes a blanketing system 140 isused with the tank 92 and a pressure relief valve 141 are used tofurther adjust and fine-tune the blended gasoline in the second mixingsection 82. Conventional tanks without the blanketing system 140 wouldrequire a floating roof which has limitations related to maximum RVPthat are dictated by additional rules and regulations. In addition, theblanketing system 140 can reduce the risk of environmental emissions andallow the pressure in the tank 92 to be greater than the vapor pressureof the gasoline and the butane and thus reduce the vaporization rate ofthe blended gasoline in the tank 92.

In certain examples, the analyzers 96, 97 can be positioned in differentpositions in the second mixing sections 82 than what is shown in FIG. 1.For example, the first analyzer 96 can be positioned between the T-pipe91 and the second mixing device 90 or upstream of inlet check valve 88.In another example, the first mixing device 77 is downstream from theinlet check valve 88. The present inventor has also contemplated thatcomponents of the first mixing section 71 may be included into thesecond mixing section 82, and vice versa.

In certain examples, the system 10 can include a final analyzer 150downstream of the outlet 100 that is in communication with thecontroller 120 to provide additional feedback to the controller 120.According, this additional feedback permits for more precise blending ofthe blended gasoline and accounts for effects to the RVP caused when theethanol injects into the final blended gasoline just before beingconveyed to the truck racks 102.

In certain examples, a system is for forming a blended gasoline fromgasoline and butane. The system includes a gasoline inlet configured toreceive the gasoline, a butane inlet that receives the butane, a firstmixing section that receives the gasoline and the butane and mixes thegasoline and the butane to form a rough blended gasoline, and a secondmixing section that receives the rough blended gasoline from the firstgasoline mixing section and further receives additional amounts of thegasoline and/or additional amounts of the butane which are further mixedinto the rough blended gasoline. An outlet dispenses a final blendedgasoline from the second gasoline mixing section. The second gasolinemixing section is downstream of the first gasoline mixing section, andthe second mixing section circulates the blended gasoline therein as theadditional amounts of the gasoline or the butane are added to the secondmixing section. In certain examples, the rough blended gasoline formedin the first mixing section has a Reid Vapor Pressure (RVP) that is lessthan a maximum allowable RVP of the final blended gasoline, andadditional amounts of the butane can be added into the rough blendedgasoline circulating in the second mixing section to thereby increasethe RVP of the blended gasoline in the second mixing section such thatthe RVP of the blended gasoline in the second mixing section approachesor is closer to the maximum allowable RVP.

In certain examples, a method of forming a blended gasoline formed withgasoline and butane includes the steps of receiving the gasoline with agasoline inlet, receiving the butane with a butane inlet, mixing thegasoline and the butane in a first mixing section to thereby form arough blended gasoline, dispensing the rough blended gasoline into asecond mixing section that is downstream from the first mixing section,circulating the rough blended gasoline in the second mixing section, andadding additional amounts of the gasoline or an the butane into theblended gasoline as the blended gasoline circulates in the second mixingsection.

In certain examples, a system for forming blended gasoline from gasolineand butane includes a gasoline inlet configured to receive the gasoline,a butane inlet configured to receive the butane, and a first mixingsection in which the gasoline and the butane mix to thereby form a roughblended gasoline. A second mixing section downstream from the firstmixing section further mixes the rough blended gasoline with additionalamounts of the gasoline or the butane until a final blended gasolineforms in the second mixing section. The final blended gasoline dispensesfrom the second mixing section via an outlet.

In certain examples, the second mixing section receives the roughblended gasoline from the first mixing section as the final blendedgasoline dispenses to the outlet. In certain examples, the second mixingsection continuously receives the rough blended gasoline from the firstmixing section as the final blended gasoline dispenses to the outlet.The rough blended gasoline formed by the first mixing section may have aReid Vapor Pressure (RVP) that is less than a maximum allowable RVP thatis present in the final blended gasoline. In certain examples,additional amounts of the butane are added to the blended gasoline inthe second mixing section to thereby increase the RVP of the blendedgasoline in the second mixing section. In certain examples, the blendedgasoline in the second mixing section circulates in the second mixingsection as the additional amounts of the gasoline or the butane mix withthe rough blended gasoline.

The system can include a first valve configured to close when the finalblended gasoline forms in the second mixing section and open when theblended gasoline in the second mixing section has not yet formed in thesecond mixing section. In certain examples, a second valve configured toopen when the final blended gasoline forms in the second mixing sectionsuch that the final blended gasoline flows to the outlet. In certainexamples, the rough blended gasoline flows through a check valve to thesecond mixing section and prevents the blended gasoline in the secondmixing section from flowing upstream into the first mixing section. Incertain examples, a controller is configured to close the first valvewhen the final blended gasoline is formed in the second mixing section.In certain examples, a gasoline analyzer is configured to analyze theblended gasoline in the second mixing section and further output datapertaining to composition of the blended gasoline in the second mixingsection to the controller; and wherein the controller closes the firstvalve based on the data. The controller can be configured to close thefirst valve and open the second valve when the final blended gasolineforms in the second mixing section. The gasoline analyzer configured toanalyze the blended gasoline in the second mixing section and furtheroutput data pertaining to composition of the blended gasoline in thesecond mixing section to the controller and the controller opens orcloses the first valve and the second valve based on the data.

In certain examples, a system for forming blended gasoline from gasolineand butane includes a gasoline inlet configured to receive gasoline suchthat the gasoline is conveyed along a first gasoline flow path and asecond gasoline flow path and a butane inlet configured to receive thebutane such that the butane is conveyed along a first butane flow pathand a second butane flow path. A first mixing section receives gasolinefrom the first gasoline flow path, receives the butane from the firstbutane flow path, mixes the gasoline and the butane to thereby form arough blended gasoline, and dispenses the rough blended gasoline. Asecond mixing section downstream from the first mixing section receivesthe rough blended gasoline from the first mixing section, receives thegasoline from the second gasoline flow path, receives the butane fromthe second butane flow path, mixes the gasoline and/or the butane withthe rough gasoline to thereby form a final blended gasoline, anddispenses the final blended gasoline; The final blended gasolinedispenses through an outlet, and a check valve is configured to permitthe rough blended gasoline to flow downstream into the second mixingsection and prevent the blended gasoline in the second mixing sectionfrom flowing upstream into the first mixing section. A gasoline analyzeris configured to analyze the blended gasoline in the second mixingsection and further output data pertaining to characteristics of theblended gasoline in the second mixing section. A controller isconfigured to open and close a first valve and a second valve based onthe data from the gasoline analyzer. The controller closes the firstvalve and opens the second valve when the final blended gasoline isformed in the second mixing section; and opens the first valve andcloses the second valve such that the blended gasoline in the secondmixing section circulates therein. The final blended gasoline is formedwhen the blended gasoline in the second mixing section has a Reid VaporPressure (RVP) that is within a threshold less than a maximum allowableRVP. The blended gasoline in the second mixing section can be circulatedin the second mixing section as the additional amounts of the gasolineor the butane mix with the rough blended gasoline.

In certain examples, a method for forming blended gasoline includes thesteps of receiving at a gasoline inlet gasoline from a gasoline supply,receiving at a butane inlet butane from a butane supply, mixing thegasoline and the butane in a first mixing section to thereby form arough blended gasoline, and dispensing the rough blended gasoline to asecond mixing section. The method can further include mixing the roughblended gasoline with additional amounts of the gasoline or the butaneuntil a final blended gasoline forms in the second mixing section anddispensing, via an outlet, the final blended gasoline from the secondmixing section.

In certain examples the method includes dispensing additional amounts ofthe rough blended gasoline to the second mixing section as the finalblended gasoline dispenses to the outlet. In certain examples the methodincludes dividing the gasoline received via the gasoline inlet such thatthe gasoline flow along a first flow path to the first mixing sectionand a second flow path to the second mixing section and dividing thebutane received via the butane inlet such that the butane flow along athird flow path to the first mixing section and a fourth flow path tothe second mixing section. In certain examples, the second mixingsection continuously receives the rough blended gasoline from the firstmixing section as the final blended gasoline continuously dispenses tothe outlet. In certain examples the method includes circulating theblended gasoline in the second mixing section as the additional amountsof the gasoline or the butane mix with the rough blended gasoline. Incertain examples the method includes analyzing, with an gasolineanalyzer, composition of the blended gasoline in the second mixingsection and outputting, with the gasoline analyzer, data correspondingthe composition of the blended gasoline to a controller and determining,with the controller, based on the data from the gasoline analyzer if thecomposition of the blended gasoline in the second mixing sectioncorresponds to the formation of the final blended gasoline in the secondmixing section. The method can further includes closing a first valve,with the controller, when the final blended gasoline has formed in thesecond mixing section and opening a second valve, with the controller,when the final blended gasoline has formed in the second mixing section.

In the present description, certain terms have been used for brevity,clarity, and understanding. No unnecessary limitations are to beinferred therefrom beyond the requirement of the prior art because suchterms are used for descriptive purposes and are intended to be broadlyconstrued. The different apparatuses, systems, and method stepsdescribed herein may be used alone or in combination with otherapparatuses, systems, and methods. It is to be expected that variousequivalents, alternatives and modifications are possible within thescope of the appended claims.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to make and use the invention. The patentable scope of the inventionis defined by the claims, and may include other examples that occur tothose skilled in the art. Such other examples are intended to be withinthe scope of the claims if they have structural elements that do notdiffer from the literal language of the claims, or if they includeequivalent structural elements with insubstantial differences from theliteral languages of the claims.

What is claimed is:
 1. A system for forming blended gasoline fromgasoline and butane, the system comprising: a gasoline inlet configuredto receive the gasoline; a butane inlet configured to receive thebutane; a first mixing section that mixes the gasoline and the butane tothereby form a rough blended gasoline; a second mixing sectiondownstream from the first mixing section that mixes the rough blendedgasoline with additional amounts of the gasoline or the butane until afinal blended gasoline forms in the second mixing section; an outletthrough which the final blended gasoline dispenses from the secondmixing section.
 2. The system according to claim 1, wherein the secondmixing section receives the rough blended gasoline from the first mixingsection as the final blended gasoline dispenses to the outlet.
 3. Thesystem according to claim 2, wherein the second mixing sectioncontinuously receives the rough blended gasoline from the first mixingsection as the final blended gasoline dispenses to the outlet.
 4. Thesystem according to claim 1, wherein the rough blended gasoline formedby the first mixing section has a Reid Vapor Pressure (RVP) that is lessthan a maximum allowable RVP of the final blended gasoline.
 5. Thesystem according to claim 4, wherein additional amounts of the butaneare added to the blended gasoline in the second mixing section tothereby increase the RVP of the blended gasoline in the second mixingsection.
 6. The system according to claim 1, wherein the blendedgasoline in the second mixing section circulates in the second mixingsection as the additional amounts of the gasoline or the butane mix withthe rough blended gasoline.
 7. The system according to claim 1, furthercomprising a first valve configured to close when the final blendedgasoline forms in the second mixing section and open when the blendedgasoline in the second mixing section has not yet formed in the secondmixing section.
 8. The system according to claim 7, further comprising asecond valve configured to open when the final blended gasoline forms inthe second mixing section such that the final blended gasoline flows tothe outlet.
 9. The system according to claim 8, further comprising acheck valve through which the rough blended gasoline is received fromthe first mixing section, wherein the check valve prevents the blendedgasoline in the second mixing section from flowing upstream into thefirst mixing section.
 10. The system according to claim 7, furthercomprising a controller is configured to close the first valve when thefinal blended gasoline is formed in the second mixing section.
 11. Thesystem according to claim 10, further comprising a gasoline analyzerconfigured to analyze the blended gasoline in the second mixing sectionand further output data pertaining to composition of the blendedgasoline in the second mixing section to the controller; and wherein thecontroller closes the first valve based on the data.
 12. The systemaccording to claim 8, further comprising a controller operably coupledto the first valve and the second valve, wherein the controller isconfigured to close the first valve and open the second valve when thefinal blended gasoline is formed in the second mixing section.
 13. Thesystem according to claim 12, further comprising a gasoline analyzerconfigured to analyze the blended gasoline in the second mixing sectionand further output data pertaining to composition of the blendedgasoline in the second mixing section to the controller; and wherein thecontroller opens or closes the first valve and the second valve based onthe data.
 14. A system for forming blended gasoline from gasoline andbutane, the system comprising: a gasoline inlet configured to receivegasoline, wherein the gasoline is conveyed along a first gasoline flowpath and a second gasoline flow path; a butane inlet configured toreceive the butane, wherein the butane is conveyed along a first butaneflow path and a second butane flow path; a first mixing section thatreceives gasoline from the first gasoline flow path, receives the butanefrom the first butane flow path, mixes the gasoline and the butane tothereby form a rough blended gasoline, and dispenses the rough blendedgasoline; a second mixing section downstream from the first mixingsection that receives the rough blended gasoline from the first mixingsection, receives the gasoline from the second gasoline flow path,receives the butane from the second butane flow path, mixes the gasolineand/or the butane with the rough gasoline to thereby form a finalblended gasoline, and dispenses the final blended gasoline; an outletthrough which the final blended gasoline dispenses; a check valveconfigured to permit the rough blended gasoline to flow downstream intothe second mixing section and prevent the blended gasoline in the secondmixing section from flowing upstream into the first mixing section; agasoline analyzer configured to analyze the blended gasoline in thesecond mixing section and further output data pertaining tocharacteristics of the blended gasoline in the second mixing section;and a controller configured to open and close a first valve and a secondvalve based on the data from the gasoline analyzer, wherein thecontroller: opens the first valve and closes the second valve such thatthe blended gasoline in the second mixing section circulates therein;and closes the first valve and opens the second valve when the finalblended gasoline is formed in the second mixing section; and wherein thefinal blended gasoline is formed when the blended gasoline in the secondmixing section has a Reid Vapor Pressure (RVP) that is within athreshold less than a maximum allowable RVP.
 15. A method for formingblended gasoline, the method comprising: receiving at a gasoline inletgasoline from a gasoline supply; receiving at a butane inlet butane froma butane supply; mixing the gasoline and the butane in a first mixingsection to thereby form a rough blended gasoline; dispensing the roughblended gasoline to a second mixing section; mixing the rough blendedgasoline with additional amounts of the gasoline or the butane until afinal blended gasoline forms in the second mixing section; anddispensing, via an outlet, the final blended gasoline from the secondmixing section.
 16. The method according to claim 15, furthercomprising: dispensing additional amounts of the rough blended gasolineto the second mixing section as the final blended gasoline dispenses tothe outlet.
 17. The method according to claim 16, further comprising:dividing the gasoline received via the gasoline inlet such that thegasoline flow along a first flow path to the first mixing section and asecond flow path to the second mixing section; and dividing the butanereceived via the butane inlet such that the butane flow along a thirdflow path to the first mixing section and a fourth flow path to thesecond mixing section.
 18. The method according to claim 16, wherein thesecond mixing section continuously receives the rough blended gasolinefrom the first mixing section as the final blended gasoline continuouslydispenses to the outlet.
 19. The method according to claim 16, furthercomprising: circulating the blended gasoline in the second mixingsection as the additional amounts of the gasoline or the butane mix withthe rough blended gasoline.
 20. The method according to claim 16,further comprising: analyzing, with an gasoline analyzer, composition ofthe blended gasoline in the second mixing section; outputting, with thegasoline analyzer, data corresponding the composition of the blendedgasoline to a controller; determining, with the controller, based on thedata from the gasoline analyzer if the composition of the blendedgasoline in the second mixing section corresponds to the formation ofthe final blended gasoline in the second mixing section; closing a firstvalve, with the controller, when the final blended gasoline has formedin the second mixing section; and opening a second valve, with thecontroller, when the final blended gasoline has formed in the secondmixing section.